WASHINGTON: A small balloon floating at a high altitude over the US state of Utah was intercepted by fighter aircraft on Friday but deemed to pose no national security or flight risk, a US-Canada military agency said, according to US media.

The North American Aerospace Defense Command (NORAD) said in a statement it had detected the balloon traveling at an altitude between 43,000-45,000 feet (13,100-13,700 metres), CBS News reported.

`The balloon was intercepted by NORAD fighters over Utah, who determined it was not maneuverable and did not present a threat to national security,` the joint agencysaid.

The US Federal Aviation Administration (FAA) `also determined the balloon posed no hazard to flight safety, according to NORAD.

`NORAD will continue to track and monitor the balloon,` it added.

An unnamed US official told CBS News the balloon had a cube-shaped box about two feet long on each side hanging below it.

In February last year, the United States shot down a huge white balloon from China after it was spotted over a series of nuclear weapons sites.

Beijing denied it was a spy balloon, saying the craft was used for weather research and had blown off-course.-AFP